Substitution of clinker with alternative constituents

Cement in Europe must be manufactured according to the harmonised standard ENⁱ 197-1 which clearly indicates the 27 common cements according to their main constituents. As mentioned, the main constituent of cement is clinker. Depending on availability, part of the clinker can be replaced with alternative constituents. Two major examples are granulated blast furnace slag, a by-product of the iron manufacturing process, and fly ashes, one of the residues generated from the combustion of coal. 

Substitution of clinker in cement is an example of the positive contribution of the European cement industry to resource management.